Chapman has missed the Cats' past two games with hamstring soreness.
He was named in Geelong's team to play Richmond last weekend, but was then ruled out a day before the match and replaced by Jordan Murdoch.
"We think (Chapman will be back), but we thought so last week as well," Geelong coach Chris Scott said on Tuesday.
"He hasn't trained fully this week; we're leaving that a little bit later. So once he's done that we'll be in a better position to judge.
"But we're extremely hopeful."
After being hampered by groin and hip problems during the early months of the year, Vardy has now played two games in Geelong's VFL team.
He showed off his enormous potential with a best-on-ground performance against Werribee at Simonds Stadium last weekend, but the Cats are refusing to accelerate their timetable for his return to their AFL side.
"His performance puts him in our best 22," Scott said. "But our conservative management means that he won't play this week.
"Our VFL team has got a bye, which is sort of unfortunate timing in a way, but he certainly won't play this week and the probability is that he won't play the following week against Port Adelaide as well."
Veteran defender Josh Hunt has also been pushing his case in the VFL but he won't be considered for AFL selection this week either.
"It is extremely conservative with Josh and probably a little bit frustrating for him," Scott said.
"He's playing well enough, but we're going to wait another week with Josh.
"I think everyone has got to remember that he missed a whole pre-season with glandular fever, so it's the combination of missing the work and being pretty sick (that is holding him back).
"We're going to take our time. We consider him a really important part of our squad and he's going to be important in the second half of the year.
"So if we're going to make a mistake we'll make one by being a little bit too slow in his build back to AFL footy."
Tom Hawkins remains troubled by the back injury that forced him to miss the Cats' round five win over the Western Bulldogs, but is not considered likely to miss Friday night's blockbuster against the Bombers.
"Medical opinion is that he's certainly not doing himself any harm by playing. He just is a little bit limited," Scott said.
"So at some point we need to decide whether he's so limited that it's affecting his performance too much, but there's no secret in the fact that he's a little bit stiff and he's not as agile as he is at his best.
"But he's still a bit of a handful close to goal."
Adam McNicol covers Geelong news for AFL.com.au. Follow him on Twitter at @AFL_AdamMcNicol
